Regional transport of PM2.5 and O3 based on complex network method and
source apportionment technology in the Yangtze River Delta,China
Abstract
Ground-level ozone(O3) and atmospheric fine particulate
matter (PM2.5) pollution are the major challenges for
continually improving air quality in the Yangtze River Delta (YRD)
region of China (Lu et al., 2020; Wei et al., 2020). Understanding
regional transport pattern of PM2.5 and
O3 pollution is essential for the development of
regional cooperative prevention and control strategies. This study shows
annual concentration of PM2.5 in the YRD decreased by
18.5% from 2015 to 2018, while average of daily maximum 8-h
average(MDA8) O3 concentration during March to October
increased by 16.3%. A complex network method is developed to
investigate regional transport of PM2.5 and
O3 in different grid cells (nodes). Source apportionment
technology in regional transport model is applied for comparing with the
results from the complex network method. Interregional and intraregional
transportation play an important role in both PM2.5 and
O3 over the YRD. The northern part of the YRD
contributes much more than other areas for PM2.5 in
winter, which accounts for about 60%,while the central part of the YRD,
especially the northern part of Zhejiang, is the largest contributor of
O3 in the YRD in summer,which accounts for about 70%.
Intraregional transport played major role in PM2.5 than
O3. The study focusing on heavily pollution episodes not
only show results between source apportionment technology and complex
network method are comparable, and also reveals both two methods pose
great potential in understanding transport pattern and air pollution
relationship, which is the foundation for emission mitigation in the YRD
region.